South Korean regulators have reportedly raided the local offices of Google as part of an ongoing investigation into claimed anti-competitive practices by the search giant.

According to the Financial Times, officials from the Korea Fair Trade Commission (KFTC) visited Google this weekend to ask questions and gather information, following complaints earlier in the year from NHN Corporation (which owns the most popular local search site) and internet portal Daum Communications.

The companies apparently complained that Mountain View was putting pressure of smartphone manufacturers not to bundle rival software on handsets, while Android made it almost impossible to remove Google’s own search tools.

Google did not respond at time of going to press, and in a statement to the Financial Times, it refused to confirm the raid, but said it was working with the KFTC to solve any problems.

"Android is an open platform, and carrier and OEM partners are free to decide which applications and services to include on their Android phones. We do not require carriers or manufacturers to include Google Search or Google applications on Android-powered devices."

The Korean authorities are more sensitive than most about technology competition, since the country has one of the highest proportion of internet users by population in the world. This is largely thanks to its extensive government-sponsored broadband system.